Fuel pump for internal combustion engines

ABSTRACT

A FUEL PUMP FOR INTERNAL COMBUSTION ENGINES, COMPRISES A HOUSING ACCOMMODATING A LOW PRESSURE PUMP AND A HIGH PRESSURE PUMP, THE LATTER BEING CONNECTED TO AN AUTOMATIC FUEL INJECTION ADVANCE DEVICE INSTALLED WITHIN THE HOUSING. A FUEL FEEDER IS INSTALLED IN THE HOUSING FOR FEEDING FUEL BATCHWISE TO THE HIGH PRESSURE PUMP AND A SLIDE VALVE OF A CENTRIFUGALLY SENSITIVE ELEMENT IS ALSO   MOUNTED IN THE HOUSING AND HYDRAULICALLY CONNECTS THE LOW PRESSURE PUMP TO THE FEEDER AND TO THE AUTOMATIC FUEL INJECTION ADVANCE DEVICE.

July 11, 1972 P. 1. ANDRUSENKO EI'AL 3,676,023

FUEL PUMP FOR INTERNAL COMBUSTION ENGINES Filed Jan. 6, 1970 43 4 5F/[if United States Patent 3,676,023 FUEL PUIVIP FOR INTERNAL COMBUSTIONENGINES Petr Ivanovich Andruseuko, Ulitsa Selskokhozyaistvennaya 3, kv.44; Kint Evgenievich Dolganov, ulitsa Patorzhiuskogo 14, kv. AlexandrIvanovich Kovalev, ulitsa Zhitomirskaya 8, kv. 25; Pavel IosipovichBerezovsky, ulitsa Rybalskaya 20, kv. 9; Vladimir Ilich Dmitrenko,Nikolai Pavlovich Shukshin, and Jury Feodosievich Gutarevich, all ofulitsa Ivana Kudri 32, Obschezhitie KADI, Kiev, U.S.S. VladimirGrigorievich Kislov, ulitsa Tekstilei 40, kv. 11; Andrei VasilievichChevtaev, polschad IH Internatsionala 31; Eduard Ivanovich Koshman,ulitsa Molodezhnaya 4, kv. 26; Vladimir Vasilievich Filippov, shosseEntuziastov 2, kv. 21; Mikhail Sergeevich Dolganov, 2 Textilny perenlok1, kv. 15; and Dmitry Ivanovich Prosnjakov, Nizhegorodskaya ploschad 3,all of Moskovskaya oblast, Noginsk, U.S.S.R.; and Alexandr BrokopievichBakharev, deceased, by Anna Mikhailovna Menshikova and JuryAlexandrovich Bakharev, both of ulitsa Ljublinskaya 39/2, kv. 31; andGalina Alexandrovna Ashikhmiua, ulitsa Novo-Alexeevskaya 4, korpus 2,kv. 59, Moscow, U.S.S.R., administrators Filed Jan. 6, 1970, Ser. No.937 Int. Cl. F04b 3/00, 19/02; G05d 13/10 US. Cl. 417-253 2 ClaimsABSTRACT OF THE DISCLOSURE A fuel pump for internal combustion engines,comprises a housing accommodating a low pressure pump and a highpressure pump, the latter being connected to an automatic fuel injectionadvance device installed within the housing. A fuel feeder is installedin the housing for feeding fuel batchwise to the high pressure pump anda slide valve of a centrifugally sensitive element is also mounted inthe housing and hydraulically connects the low pressure pump to thefeeder and to the automatic fuel injection advance device.

The present invention relates to fuel pumps for internal combustionengines.

Known in the prior art is a fuel pump for internal combustion engines,where in a high-pressure pump with automatic fuel injection advance isconnected to a low-pressure pump through a fuel feeder and a centrifugalsensitive element.

The centrifugal sensitive element is constituted as rotating weightswhich move under the action of the centrifugal force and act through asystem of levers on the fuel feeder.

A disadvantage of the above fuel pump is that an insignificant wear ofthe parts of the sensitive element and the levers connecting it to thefuel feeder disturbs the stability of the fuel feed characteristic.

It is an object of the present invention to eliminate the abovedisadvantage.

The principal object of the present invention is to provide such a fuelpump which will ensure a stable fuel feed characteristic.

This object is achieved by the provision of a fuel pump for internalcombustion engines, in which, according to the invention, thehigh-pressure pump, provided with automatic fuel injection advance, isconnected to the lowpressure pump through a fuel feeder and acentrifugal sensitive element.

According to the present invention, the centrifugal sensitive element isconstituted as a slide valve rotating about an axis perpendicular to thedirection of its movement, and having its center of gravity displacedrelative to this axis of rotation, said control valve hydraulicallyconnect- 3,676,023 Patented July 11, 1972 ing the low-pressure pump tothe fuel feeder and the automatic fuel injection advance device.

In a fuel pump of the rotary type it is expedient to install the slidevalve in the rotor at right angles to its axis of rotation.

The details of the present invention will become more fully apparentfrom a consideration of the following description of an exemplaryembodiment thereof, taken in conjunction with the accompanying drawings,in which:

FIG. 1 is a longitudinal section of the fuel pump for internalcombustion engines according to the present invention; and

FIG. 2 is a cross section taken along line II-II of FIG. 1.

A housing 1 (FIG. 1) of the fuel pump accommodates a high-pressure pump2 provided with a rotary distributor 3 having plungers 4 radiallyinstalled thereon, said plungers bearing against a cam ring 6 throughpushers 5.

The cam ring 6 has uniformly spaced cams 7 (FIG. 2) provided at the sideof the plungers 4, the cams 7 interacting via the pushers 5 with theplungers 4.

An automatic fuel injection advance device 8 is connected with the camring 6. The automatic device 8 comprises a piston 9 connected by meshingof rack teeth thereon with the cam ring 6, a spring 10 on which a washer11 rests with an adjusting screw 12 for limiting the movement of thepiston 9 in one direction, and an adjusting screw 13 for limiting themovement of the piston 9 in the opposite direction.

The housing 1 also accommodates a low-pressure gear pump 14 connected tothe rotary distributor 3.

The rotary distributor is provided with an opening 15 arrangedperpendicular to its axis of rotation. In this opening there isinstalled a sensitive element, fashioned as a slide valve 16 which atone side has an enlarged head 17, due to which the center of gravity ofthe valve 16 is displaced relative to the axis of rotation of the rotarydistributor 3. The middle portion of the slide valve 16 is provided withan annular groove 18, a radial duct 19 and an axial duct 20. The valve16 is closed at both sides with caps 21 and 22.

The housing 1 accommodates a fuel feeder 23 comprising a sleeve 24 witha calibrated triangular opening 25, and a piston 26, on whose surface anannular groove 27 is formed which is provided with radial openings 28.One side of the piston 26 is loaded by a spring 29 and is connectedthrough the latter to a control lever 30, whereas the other side isprovided with an adjusting screw 31 which limits the stroke of thepiston 26.

The fuel pump operates as follows:

Upon rotation of the rotary distributor 3, the low-pressure pump 14communicating therewith delivers fuel from a tank (not shown) along aduct 32 into a space 33 defined by the annular groove 18 of the slidevalve 16 and the surface of the opening 15. A portion of the fuel flowsalong a duct 34 into the suction space of the low-pres sure pump 14. Theremaining portion of the fuel flows from the space 33 along a duct 35 tothe feeder 23 and the automatic fuel injection advance device 8.

The pressure of the fuel in the space 33 and in the space under the cap21 communicating with the latter via the ducts 19 and 20 depends on theratio of the flow areas of the ducts 32 and 34. This ratio isautomatically set by slide valve 16 depending on the magnitude of thecentrifugal force acting thereon and the force induced by the pressureof the fuel under the cap 21, which prevents movement of the valve 16.As a result of the interaction of these forces the valve 16 is set in aposition wherein the pressure of the fuel under the cap 21 becomes equalto the centrifugal force acting on the valve 16 divided by itscross-sectional area.

The spring 37 serves for initial setting of the valve 16.

Thus, the pressure of the fuel delivered along the duct 35 to the feeder23 and the automatic fuel injection advance device 8 changes inproportion to the square of the speed of the rotary distributor 3.

The plungers 4 of the rotary distributor 3 move apart under the actionof the centrifugal force. By this movement a duct 38 will havecommunicated with the corresponding opening of a sleeve 39 connected viaa duct 40 to feeder 23. Thus injection of the fuel takes place.

Upon further rotation of the rotary distributor 3 the ducts 38 and 40are disconnected. At this moment rollers 41 of the pusher 5 run onto thecams 7 of the cam ring 6, and the plungers 4, moving toward each other,compress the fuel and, when a delivery duct 42 coincides with acorresponding high-pressure pipe connection 43, delivers it to thenozzle of the engine.

The amount of fuel delivered to the plungers 4 is determined by the flowarea of the opening 25in the sleeve 24 of the feeder 23. The flow areaof the opening 25 depends on the position of the edge of the annulargroove 27 of the piston 26. Depending on the required amount of fuel tobe delivered, the position of the piston 26 is regulated by means of theadjusting screw 31. The operational speed of the engine is determined bythe degree of tightening of the spring 29, which depends on the positionof an adjusting screw 44.

When the rated speed is reached, the pressure of the fuel deliveredalong the duct 35 acts on the piston 26 and, overcoming the resistanceof the spring 29, moves the piston. Then the edge of the groove 27 ofthe piston 26 begins to close the opening 25 in the sleeve 24 of thefeeder 23, reducing the flow area of this opening.

The automatic fuel injection advance device 8 ensures a change in theangle of fuel delivery advance by means of the piston 9 of the device,which, moving under the pressure of the fuel fed along the duct 35,turns the cam ring 6.

At low speeds of the engine, the pressure of the fuel cannot overcomethe resistance of the spring of a valve 45 and the piston 9 will be inits extreme right-hand position, determined by the adjusting screw 13,ensuring the maximum lag in the angle of fuel delivery commencement.Upon an increase in the speed, the fuel passing through the valve 45,moves the piston 9 until it rests against the washer 11, and compressesthe spring 10, turning at the same time the cam ring 6 in the directionincreasing the angle of injection advance. The maximum angle ofinjection advance is determined by the position of the screw 12.

What is claimed is:

1. A fuel-injection pump apparatus for an internal combustion engine,said apparatus comprising a high-pressure pump stage, a fuel-pressureregulator, a fuel feeder for said stage, a low-pressure feed pumpincluding inlet and outlet chambers, inlet and outlet ducts coupled tosaid chambers, said low-pressure feed pump being connected via said fuelpressure regulator to said high-pressure pump stage, the fuel pressureregulator comprising a slide valve member and a spring associated withsaid valve member, said valve member being adapted to rotate about anaxis perpendicular to the direction of its movement, the center ofgravity of said valve member being eccentric relative to said axis, saidvalve member including a head at one end thereof, being provided with anannular groove in a portion thereof midway between its ends, a capcovering said head and a space being provided under the cap incommunication with said annular groove, said groove having edgespartially closing the inlet and outlet ducts connected to the outlet andinlet chambers of said low-pressure feed pump, said valve membercontrolling the fuel pressure in said groove and in the space under saidcap by changing the ratio between the cross-sectional area of the inletduct and that of the outlet duct, and automatically coming into an axialposition which corresponds to a state of balance between said fuelpressure and the centrifugal force of said valve and the force of saidspring, said annular groove communicating with said fuel feeder for thehigh-pressure pump stage to provide accurate metering of the fuel due toa high stability of the centrifugally controlled fuel pressure.

2. A fuel-injection pump as claimed in claim 1, wherein saidhigh-pressure pump stage includes an automatic fuel injection advancemeans including a piston and a spring with a gap between the same, saidpiston moving due to said gap into a position of the retard injectionfor starting of the engine.

References Cited UNITED STATES PATENTS 3,289,590 12/1966 Hutcheon417--253 X 3,416,505 12/ 196 8 Barber 417--2l8 2,916,029 12/1959 Kemp123-43913 F FOREIGN PATENTS 997,414 7/1965 Great Britain 4l74621,149,199 5/1963 Germany 4l7462 CARLTON R. CROYLE, Primary Examiner R.E. GLUCK, Assistant Examiner U.S. Cl. X.R. 137-56; 4l7462 UNITED STATESPATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 ,676 ,023 DatedJuly 11 i977 Inventor-(s) Petr -Ch Andrusenko 61: a1,

It is certified that error appears in the above-identified patent andthat said Letters Patent are hereby corrected as shown below:

In the heading to the printed specification, liness lQ and 20, "AlexandrBrokopievich Bakharev" should read Alexandr Prokopievich Bakharev aSigned and sealed this 27th day of February 1973.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Commissioner of PatentsAttesting Officer

